Shrinking a LUN without the proper steps performed at the OS level can cause unrecoverable data loss. You should only shrink a LUN who's operating system supports resizing the file systems and partition tables to a smaller size.
- Resize the file system (and volume if necessary) inside the LUN to the new size using the host operating system's native tools. Contact your OS or file system vendor for specific steps.
- Resize the partitions inside the LUN. You may again refer to your OS vendor's documentation on how to perform this step.
- Shrink the LUN. You can do this from the ONTAP Cluster Shell by decreasing the size as shown in this example:
lun resize -vserver vs3 -volume vol3 -lun lun1 -size 75GB
- Your host OS may require you to rescan your HBAs in order to see the new size. If so, perform that step now.
NetApp also offers LUN management tools such as SnapDrive for Windows, SnapDrive for UNIX, and SnapCenter Plugins which can automate all of the above.